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If a constant torque acts on a body, the...

If a constant torque acts on a body, the body?

A

will acquire a linear acceleration according to Newton's second law of motion

B

will acquire angular momentum

C

will rotate with a constant angular velocity

D

the body will move with a constant velocity or remain motion less in accordance with Newton's first law of motion.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question "If a constant torque acts on a body, the body?" we will analyze the implications of a constant torque on the motion of the body step by step. ### Step-by-Step Solution: 1. **Understanding Torque**: Torque (τ) is defined as the product of the force (F) applied and the distance (r) from the pivot point where the force is applied. Mathematically, it is given by: \[ τ = r \times F \] If a constant torque is applied, it means that the torque value does not change over time. **Hint**: Remember that torque is related to the rotational effect of a force applied at a distance from the axis of rotation. 2. **Effect of Constant Torque**: According to the rotational analog of Newton's second law, the net torque acting on a body is equal to the moment of inertia (I) of the body multiplied by its angular acceleration (α): \[ τ = I \cdot α \] If the torque is constant, then the angular acceleration will also be constant. **Hint**: Think about how constant torque leads to constant angular acceleration, which affects the angular velocity of the body. 3. **Angular Velocity and Angular Acceleration**: The relationship between angular velocity (ω), angular acceleration (α), and time (t) can be expressed as: \[ ω = ω_0 + α \cdot t \] where \(ω_0\) is the initial angular velocity. Since α is constant, the angular velocity will change over time as long as torque is applied. **Hint**: Consider how the body’s angular velocity changes over time due to the constant angular acceleration. 4. **Angular Momentum**: Angular momentum (L) is given by: \[ L = I \cdot ω \] Since the body is experiencing a constant torque, it will also experience a change in angular momentum over time. The angular momentum will increase as the body rotates. **Hint**: Remember that angular momentum is directly related to both the moment of inertia and the angular velocity. 5. **Conclusion**: Given that a constant torque results in a constant angular acceleration, which in turn leads to a change in angular velocity and an increase in angular momentum, the most appropriate answer to the question is: - The body will acquire angular momentum. ### Final Answer: **The body will acquire angular momentum.**
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